ASTM B381: Specifications for Titanium Flanges and Forgings

ASTM B381 is a standard specification for titanium and titanium alloy forgings, including flanges. It covers various aspects of the manufacturing process, chemical composition, mechanical properties, and quality requirements for titanium forgings used in industrial applications. While ASTM B381 does not specifically address flanges, it provides essential guidelines for the production and quality assurance of titanium forgings, which can be applied to the manufacture of titanium flanges. Here are some key aspects covered by ASTM B381 relevant to titanium flanges:

1. Chemical Composition: ASTM B381 specifies the chemical composition requirements for titanium and titanium alloy forgings, including the maximum allowable percentages of elements such as oxygen, nitrogen, carbon, hydrogen, iron, and others. These composition requirements ensure that the titanium material used for flanges meets the desired specifications and performance criteria.

2. Mechanical Properties: The standard defines mechanical property requirements, including tensile strength, yield strength, elongation, and reduction of area, for titanium forgings. These properties are crucial for determining the strength, ductility, and toughness of titanium flanges under various operating conditions.

3. Heat Treatment: ASTM B381 outlines the heat treatment procedures for titanium forgings to achieve the desired mechanical properties and microstructure. Heat treatment processes such as annealing, solution treatment, and aging may be specified depending on the alloy composition and intended application of the forgings.

4. Dimensions and Tolerances: The standard provides dimensional tolerances for titanium forgings, including flanges, ensuring that they meet the required specifications and are compatible with mating components in piping systems. It covers parameters such as diameter, thickness, width, length, and surface finish.

5. Quality Assurance: ASTM B381 includes requirements for quality assurance and testing of titanium forgings to ensure their conformance to specified standards and performance criteria. These may include non-destructive testing (NDT), such as ultrasonic testing (UT) and dye penetrant testing (PT), as well as mechanical testing and inspection of dimensions and surface quality.

6. Certification and Marking: The standard outlines requirements for certification and marking of titanium forgings, including identification of the material grade, heat number, manufacturer's name or logo, and other relevant information. This helps ensure traceability and accountability throughout the supply chain.

While ASTM B381 does not specifically address titanium flanges, manufacturers producing titanium flanges typically adhere to the requirements and specifications outlined in ASTM B381 for the production of titanium forgings. This ensures that titanium flanges meet the necessary standards for chemical composition, mechanical properties, dimensional tolerances, quality assurance, and certification, providing confidence in their performance and reliability in industrial applications